Monte Carlo Simulation for X-ray Spectrum on Industrial Molybdenum Target Units
GE Shuang1,2,WU Jin-jie2,QIU Xiao-ping1,CHEN Fa-jun2
1. Department of Nuclear Science and Technology, University of South China, Hengyang, Hunan 421001, China
2. National Institute of Metrology, Beijing 100029, China
Abstract：The Monte Carlo simulation program EGSnrc is adopted to simulate components of industrial X-ray mammography target units and the transportation process for photons which is produced by 28 keV electron beam bombarding a molybdenum target . The particle phase space files which is gained on a plane away the focus at 50 cm and a radius 5 cm radiation field.The information, like particle fluence, energy spectrum distribution, angular distribution, average energy and so on,can be obtained by the analysis of the phase space files. Simulated the molybdenum target X-ray spectrum distribution is affected by filter material and tube voltage. The mean energy of molybdenum filtration is less than rhodium filter, but the impact of higher energy part is greater than the rhodium filter, with tube voltage increasing, the effective production rate of photon and the mean energy are all increased.Under the four groups radiation quality conditions, the mean energy of mammography X-ray spectra are each 16.0, 16.6, 17.0, 17.8 keV, and close to the experimental measurements, the relative error in less than 1%.
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2015, Vol. 36 
